Eastern Marsh Harriers

Eastern Marsh Harriers breed at Yeyahu Nature Reserve in Beijing. They are one of the star birds of any visit from late March through to October. The spring males are simply stunning and quite different from the closely-related Western Marsh Harrier, some almost resembling one of the other regional specialities, Pied Harrier. Adult females also look very different from Western Marsh and, in my experience, it is only really juveniles/first winters/probable 2 cy birds that could be mistaken for Western Marsh.

I couldn’t find any literature on aging or sexing Eastern Marsh Harriers (is there any out there?). So here are some images of adult males, females, a probable first summer and juvenile birds with some personal comments. Comments from others are very welcome. Having had a bit of difficulty separating a dark juvenile Pied recently, I have much to learn about these wonderful raptors.

Thanks Ken. I wasn’t aware of the Finnish bird but, having just looked it up on BirdForum, I have to say that it looks pretty good! I don’t know for sure whether Western can look like that (I certainly haven’t seen a Western looking anything like the Finnish bird) but I can say that the lack of a dark trailing edge on the underwing is ok for male Eastern (as my bird shows). Interesting!

Thanks John. Yes, now is a great time to get to grips with juveniles.. Structure is a clue (Pied being slimmer and smaller headed/billed) but that’s not always obvious on a lone individual, especially in varying weather conditions. Lots to learn!